Reusable PerformanceProgressBar

I'm currently writing an PivotApplication that'll need a PerformanceProgressBar in several different PivotItems. I was wondering: instead of creating a different progress bar for each PivotItem, is there a simple way I can share a single one between each PivotItem?

You can place pivot and pivot items in a grid, and once you have populated all pivot items, place a progress bar in the outer grid, it should encompass all pivot pages. Not sure why you would want to do that but it can be done.
Eg:
<Grid x:Name="LayoutRoot" Background="Transparent">
<Grid.Resources>
<loc:VisibilityToBooleanConverter x:Key="VisibilityToBooleanConverter"/>
<loc:InvVisibilityToBooleanConverter x:Key="InvVisibilityToBooleanConverter"/>
</Grid.Resources>
<!--Pivot Control-->
<controls: Pivot Name="Pivot1" Title="1">
<!--Pivot item one-->
<controls: PivotItem Header="1">
<Grid>

when you show the progressbar, you are hinting to user to wait and not do any action.. each progressbar is an indication of an activity which might be unique to a pivot screen. to have one in general is very generic :)